Portable devices, such as mobile phones, tablet devices, digital cameras, and other types of computing and electronic devices can include a biometric authentication sensor that a user can simply touch with a digit, such as a thumb or finger, to access a device. A biometric authentication sensor is typically positioned offset relative to the integrated display of an electronic device, and the display lens that covers the display extends over the sensor area offset from the display. However, the display lens is designed with an opening to accommodate access to the biometric authentication sensor so that a user can place a digit, such as a thumb or finger, on the sensor, which then images the biometric input sample for user authentication.
Also, a biometric authentication sensor needs to first be activated to image the biometric input sample, such as requiring the user to initiate a device on-button, or other type of activation of the device, which then initiates activation of the biometric authentication sensor. This type of sensor activation can include “wake on finger touch” to “wake-on” the biometric authentication sensor, which requires the sensor to always be in a powered or semi-powered state monitoring for a sensor touch. This can contribute to drain the battery or other power source of a portable device.
It is beneficial to place a biometric authentication sensor directly under a large lens or other non-conductive surfaces. Reasons for this configuration include aesthetic purposes, water resistance, smoothness, and cost. Present arrangements and technologies do not allow for low power sensor wake-on function at a sensor area under a non-conductive surface.